Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
phuc van » thuc van, phuc va, chuc van
cau phuc » cau truc, chau phu, huu phuc
hanh de » hanh ve, hanh kem
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
sang ma » tang ma, nang ma, sang tao
nang xa » nang x, lang xa, nang ma
ve cau » ke cau, va cau, ve cac
de cua » le cua, te cua, dieu cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ky ((nang xa) or (sang ma)) hoi. hieu ve cau phuc van hanh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky ((nang xa) OR (sang ma)) hoi. hieu ve cau phuc van hanh de cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky ((nang xa) or (sang ma)) hoi. hieu ve cau phuc van hanh de cua tre*".